题解 | #从单向链表中删除指定值的节点#

/*
 * 时间: 2021-05-31 23:13
 * 分析: 1) 题干中链表的表示方法, 构造单项链表即可
 * 思路: 
 */
import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        while (sc.hasNextInt()) {
            int cnt = sc.nextInt();
            Node head = new Node(sc.nextInt());
            // 错写成 i < cnt
            for (int i = 0; i < cnt - 1; i++) {
                head.insert(new Node(sc.nextInt()), sc.nextInt());
            }
            head = head.delete(sc.nextInt());

            if (head == null) {
                System.out.println("null");
            }

            Node iter = head;
            while (iter != null) {
                System.out.print(iter.val + " ");
                iter = iter.next;
            }
            System.out.println();
        }
    }
}

class Node {
    int val;
    Node next;

    Node(int val) {
        this.val = val;
        this.next = null;
    }

    public void insert(Node node, int target) {
        Node cursor = this;
        // 错写成 target != node.val
        while (target != cursor.val) {
            cursor = cursor.next;
        }

        node.next = cursor.next;
        cursor.next = node;
    }

    public Node delete(int val) {
        Node cursor = this;
        // 节点头
        if (cursor.val == val) {
            return cursor.next;
        }

        while (cursor.next != null) {
            Node last = cursor;
            cursor = cursor.next;
            if (cursor.val == val) {
                last.next = cursor.next;
                break;
            }
        }
        return this;
    }
}